整体二分(模板一)静态区间第K大

  1 #define IOS ios_base::sync_with_stdio(0); cin.tie(0);
  2 #include <cstdio>//sprintf islower isupper
  3 #include <cstdlib>//malloc  exit strcat itoa system("cls")
  4 #include <iostream>//pair
  5 #include <fstream>//freopen("C:\Users\13606\Desktop\Input.txt","r",stdin);
  6 #include <bitset>
  7 //#include <map>
  8 //#include<unordered_map>
  9 #include <vector>
 10 #include <stack>
 11 #include <set>
 12 #include <string.h>//strstr substr strcat
 13 #include <string>
 14 #include <time.h>// srand(((unsigned)time(NULL))); Seed n=rand()%10 - 0~9;
 15 #include <cmath>
 16 #include <deque>
 17 #include <queue>//priority_queue<int, vector<int>, greater<int> > q;//less
 18 #include <vector>//emplace_back
 19 //#include <math.h>
 20 #include <cassert>
 21 #include <iomanip>
 22 //#include <windows.h>//reverse(a,a+len);// ~ ! ~ ! floor
 23 #include <algorithm>//sort + unique : sz=unique(b+1,b+n+1)-(b+1);+nth_element(first, nth, last, compare)
 24 using namespace std;//next_permutation(a+1,a+1+n);//prev_permutation
 25 //******************
 26 clock_t __START,__END;
 27 double __TOTALTIME;
 28 void _MS(){__START=clock();}
 29 void _ME(){__END=clock();__TOTALTIME=(double)(__END-__START)/CLOCKS_PER_SEC;cout<<"Time: "<<__TOTALTIME<<" s"<<endl;}
 30 //***********************
 31 #define rint register int
 32 #define fo(a,b,c) for(rint a=b;a<=c;++a)
 33 #define fr(a,b,c) for(rint a=b;a>=c;--a)
 34 #define mem(a,b) memset(a,b,sizeof(a))
 35 #define pr printf
 36 #define sc scanf
 37 #define ls rt<<1
 38 #define rs rt<<1|1
 39 typedef pair<int,int> PII;
 40 typedef vector<int> VI;
 41 typedef long long ll;
 42 const double E=2.718281828;
 43 const double PI=acos(-1.0);//
 44 const ll INF=(1LL<<60);
 45 const int inf=(1<<30);
 46 const double ESP=1e-9;
 47 const int mod=(int)1e9+7;
 48 const int N=(int)1e6+10;
 49 
 50 PII a[N];
 51 int ans[N];
 52 int c[N],maxn,now;
 53 int lowbit(int n){return n&(-n);}
 54 void add(int i,int t)
 55 {
 56     while(i<=maxn)
 57     {
 58         c[i]+=t;
 59         i+=lowbit(i);
 60     }
 61 }
 62 int Sum(int i)
 63 {
 64     int sum=0;
 65     while(i)
 66     {
 67         sum+=c[i];
 68         i-=lowbit(i);
 69     }
 70     return sum;
 71 }
 72 struct node
 73 {
 74     int l,r,k,id;
 75 }q[N],temp[N];
 76 
 77 void solve(int l,int r,int ql,int qr,int n)
 78 {
 79     int L=ql,R=qr,mid=l+r>>1;
 80 
 81     if(l==r)
 82     {
 83         //    pr("1
");
 84         for(int i=ql;i<=qr;++i)ans[q[i].id]=l;
 85         return;
 86     }
 87 
 88     while(a[now+1].first<=mid&&now+1<=n)++now,add(a[now].second,1);//这边保证了一个位置最大经过3次;
 89     while(now&&a[now].first>mid)add(a[now].second,-1),--now;//        全清空会TLE;
 90 
 91     for(int i=ql;i<=qr;++i)
 92     {
 93         int res=Sum(q[i].r)-Sum(q[i].l-1);
 94         if(res>=q[i].k)temp[L++]=q[i];
 95         else temp[R--]=q[i];
 96     }
 97     for(int i=ql;i<=qr;++i)
 98         q[i]=temp[i];
 99     if(L>ql)solve(l,mid,ql,L-1,n);
100     if(R<qr)solve(mid+1,r,R+1,qr,n);
101 }
102 
103 int main()
104 {
105     int T;
106     sc("%d",&T);
107     while(T--)
108     {
109         int n,m;
110         sc("%d%d",&n,&m);
111         for(int i=1;i<=n;++i)sc("%d",&a[i].first),a[i].second=i,c[i]=0;
112         maxn=n;
113         now=0;
114         for(int i=1;i<=m;++i)
115             sc("%d%d%d",&q[i].l,&q[i].r,&q[i].k),q[i].id=i;
116         sort(a+1,a+1+n);
117         solve(-inf,inf,1,m,n);
118         for(int i=1;i<=m;++i)
119             pr("%d
",ans[i]);
120     }
121     return 0;
122 }
123 
124 /**************************************************************************************/
原文地址:https://www.cnblogs.com/--HPY-7m/p/11913250.html